The previous code was detecting the presence of "--" by looking only at
argument 1. As a result, "git checkout foo bar --" was interpreted as an
ambiguous file/revision list, and errored out with:
error: pathspec 'foo' did not match any file(s) known to git.
error: pathspec 'bar' did not match any file(s) known to git.
error: pathspec '--' did not match any file(s) known to git.
This patch fixes it by walking through the argument list to find the
"--", and now complains about the number of references given.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr> Signed-off-by: Junio C Hamano <gitster@pobox.com>